Oroxylin A induces G2/M phase cell-cycle arrest via inhibiting Cdk7-mediated expression of Cdc2/p34 in human gastric carcinoma BGC-823 cells.
We reported previously that oroxylin A, a natural product isolated from Scutellariae Radix, was a potent apoptosis inducer of human hepatoma HepG2 cells. In this study, cell-cycle arrest of BGC-823 human gastric carcinoma cells caused by oroxylin A has been investigated. Based on our 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay and flow cytometric analysis, treatment of BGC-823 cells with growth suppressive concentrations of oroxylin A caused an irreversible arrest in the G2/M phase of the cell cycle. Western blot analysis demonstrated that oroxylin A-induced cell-cycle arrest in BGC-823 cells was associated with a significant decrease in cdc2/p34, cyclin B1 and cyclin A expression. In addition, oroxylin A-treated cells decreased the expression of Cdk7, which was responsible for the low expression of M phase promoting factor (cyclin B1/Cdc2). The results suggested that oroxylin A induced G2/M phase cell-cycle arrest via inhibiting Cdk7-mediated expression of Cdc2/p34 in human gastric carcinoma BGC-823 cells.
Yang
Yong
Y
Jiangsu Key Laboratory of Carcinogenesis and Intervention (China Pharmaceutical University), Nanjing 210009, People's Republic of China.
Hu
Yang
Y
Gu
Hong-Yan
HY
Lu
Na
N
Liu
Wei
W
Qi
Qi
Q
Zhao
Li
L
Wang
Xiao-Tang
XT
You
Qi-Dong
QD
Guo
Qing-Long
QL
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D015153:Blotting, Western; D016203:CDC2 Protein Kinase / Q000187:drug effects* / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D019925:Cyclin A / Q000187:drug effects / Q000378:metabolism; D019926:Cyclin B / Q000187:drug effects / Q000378:metabolism; D056744:Cyclin B1; D018844:Cyclin-Dependent Kinases / Q000187:drug effects / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology*; D005434:Flow Cytometry; D016195:G2 Phase / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D013274:Stomach Neoplasms / Q000188:drug therapy / Q000473:pathology; D013778:Tetrazolium Salts; D013844:Thiazoles; D000095043:Cyclin-Dependent Kinase-Activating Kinase
D000972:Antineoplastic Agents, Phytogenic; C534699:CCNB1 protein, human; D019925:Cyclin A; D019926:Cyclin B; D056744:Cyclin B1; D005419:Flavonoids; D013778:Tetrazolium Salts; D013844:Thiazoles; C080669:5,7-dihydroxy-6-methoxy-2-phenylchromen-4-one; D016203:CDC2 Protein Kinase; D018844:Cyclin-Dependent Kinases; C022616:thiazolyl blue; D000095043:Cyclin-Dependent Kinase-Activating Kinase; C000722416:CDK7 protein, human